How to Make the Roof Cleaner used in the Video

A little background on how I started Roof Sparkle. A company that’s make cleaning products asked me if I could make a video for some of their cleaning products. Now I won’t go into details on who they are but they had a roof cleaner that involved the use a power washer. Big red flag in my eyes. Being a contractor for years, I knew right off the bat that was a big no-no.

So the next question I asked myself what’s that black stuff on the roof. Well, it’s mold. And what kills mold, bleach right. Well as true as that is bleach is only made up of 5-6% Sodium Hypocrite. And that’s great for your whites and around the house but not on your roof.

For the roof, you will need something a lot more powerful. Some of you may know it as pool shock. This is made up of 12% by weight “Sodium Hypochlorite”. But because it’s as thin as water it will run right off the roof and not really have the time (five minutes) to do it’s job. So we have to thicken up a bit. The best way, add some liquid dish soap to the mix to help the SH stick to the roof for more than one second. You can go into any pool supply and ask for a gallon of shock, for about $4.00 per gallon. This is just a heavy-duty version of household bleach. And no Walmart does not sell this or the big box stores.

Now, of course, we buy it from the manufacturer and by the truckloads at a time.

Applying It

When we started we used a regular bug sprayer. Use a three gallon pump sprayer, use one gallon of SH and two gallons of water (H2O) add about 4 oz. of liquid dish soap and spray from the roof top working your way down.

DON’T

clean your roof when it super hot out in the baking sun. It will kill the SH and dry before it’s clean.

Don’t touch the SH with bare hands. Wear gloves and eye protection.

Don’t spray your roof down first with water to cool it off.

Dirty Roof

Clean Roof

How to Make the Roof Cleaner used in the Video

3.74 (74.74%) 95 votes

Comments

About The Author

dominick

A residential and commercial contractor for over 35 years. Created askmediy.com 9 years ago. Making home improvement videos. Over 65k subscribers with more than 28 million views on Youtube.com Started contracting in 1987 Built over 300 homes. Licensed electrician in NY, cabinet maker, with fine woodworking skills, Very versed in all phases of home improvements. From foundations to a sink faucet.

Related Posts

138 Comments

No biggie really. As long as it’s a good rain and rinses it well you should be fine.

ShawnJune 29, 2014

What if you apply your mix to roof and get a surprise rain? What happens to plants with run off? Even if you soaked during or prior. Also, not having the gutters to bag to protect them. Here in Florida it happens a lot. Sometimes can rain in the back yard and not in the front yard.

I just did my roof today using pool chlorine 1 part and water 2 parts. Soaked the roof with pump sprayer and kept it wet with garden hose misting it. Im in FL and it is hot and sunny today. All the dark brown and black rinsed off in few minutes like you said. Quick and easy process.

Yesterday I tried Krud Kutter I bought at Lowes – $25 for two gallons. That stuff stained my shingles brown and did not work at all. Your method fixed everything. Thank you for great advice.

Yes you could use 50/50 of SH and water. 50 gallons I use a small size to 50 gallons. Dawn works the best.

rick eberlyJune 18, 2014

Hi there
I am getting ready to do my shingle roof in florida and I want to know if I can use a 50/50 solution of liquid chlorine and water and then, add the dish soap. By the way, the tank I rented to mix it all up is 50 gallons. so how much dish soap should I use. any help would be great.

Thank you so much. Is the pressure is there sure. However the SH will rust out the pump in no time. So make sure you clean it with water afterwards.

Tim FaulsJune 13, 2014

Great videos and Q&A info…outstanding Dominick.

Can we use a 5 gallon bucket & Wayne PC2 115-Volt 340 GPH Portable Transfer Water Pump, Bronze to send your mixed 3 gallon solution up onto the roof without having to climb up on the roof? I am not enthusiastic about climbing up on the roof.

There is no option when it comes to SH and Oxygen bleach. SH is the only way. And no, I’ve tried everything. Either too dangerous or they just don’t work.
Look for my video on how to prevent moss. You would use copper flashing.

NickMay 29, 2014

Dominick,

Thanks for the great information on the moss removal. There is so much information available on the net I really appreciate your straight forward approach and advice. I am trying to decide between your method or using oxygen bleach cleaners with sodium percabonate & soda ash. Have you ever used these types of cleaners? Also what do you recommend for preventing moss from coming back?

CathyMay 25, 2014

I just did my siding on the north side of my house, using Dawn liquid and a 4 litre sprayer. I have never seen my siding look so great since the day it was installed! Thanks so much. I’ve tried scrubbing some of the stains before with different products, to no avail. I can’t believe this was so easy. The only unintended consequence is that my wood deck underneath is now really clean where the runoff was, so I’m going to spray the whole thing. This works out really well, as I need to re-stain it anyway. I can’t wait to try this on the roof. I had a quote to get my shingles redone and it was going to be $4000, when really there’s nothing wrong with them other than black streaks. This is a much better way to go, and saves my wallet. Thanks again!

Yes we use Dawn most of the time. But remember you’re not using the soap to clean. It’s only there to help hold the SH on the roof longer rather than being too thin and just running right off.

CathyMay 23, 2014

Thanks for the great info, Dominick! I’m looking forward to trying this out. One question though – I have a bottle of Sunlight dish soap that says on the back ‘do not mix with chlorine bleach’, but my bottle of Dawn does not say that. The warning on the first has me worried though! What brand have you used? Have you ever used Dawn? I’d hate to have some I intended chemical reaction! Thanks.

Yes to a extent, but you wouldn’t want it to dry on the roof. So rinsing it is always a better choice.

BonnieMay 16, 2014

great site Dominick! I live in central Canada where it is now 10C-15C during the daytime. It gets close to 0C at night.
I plan on applying your solution to my roof this weekend. questions: Do I need to rinse it off, or just wait for mother nature to do her magic with rain? Will the strength of the SH just dissipate over time and not harm my grass if I leave it on the roof without rinsing? If I do have to rinse, how long do you leave the SH on before the rinse? Can I use cold water from the tap?
I am a lady afraid of heights trying this myself, so the least amount of time on the roof the better!! Thanks.

It really depends on how bad the roof is. If it’s really bad you could do 50/50 But no. The smallest I know is 1/3

John MMay 9, 2014

Hello Dominic first of all great site and thanks for all the help. Second I am having trouble finding a 3 gallon pump sprayer and if I do find one it is either bigger or expensive so I was going to get a 2 gallon one if that would work. Any idea how much shock and water and dish soap to use to get the mixture right. I got the 12.5 shock from pool place I have the The dish soap and water but I don’t know ratios go the 2 gallon pump sp5rsyer. I figured I would run it by you see what you thought or if you had another idea

Hi, sorry for the delay. Your question came in as spam for whatever reason..

The SH wont harm the deck but clean it very well. I’ve used it with a big mop before and it came out great. But then again, that was for me. The Poconos ?. Heck we’re not that far apart at all. I’m there almost every weekend.

JustinMay 4, 2014

I don’t understand “weight not volume”… isn’t 1 gallon SH and 2 gallon H20 both volume measurements? How do we get 1 gallon of weight for SH and 2 gallons of weight for H20? Sorry I just want to make sure I get it right. Thanks!

Caryn ElizabethApril 28, 2014

I have a composite deck at the base of my roof area I’ll be treating. The deck also has mold from it being on the north side. Will this solution be okay on the decking material? It’s like a trex deck but not that brand. Actually, forgot the name. duh! Can I try it on my front small wood deck to clean off the black from years of it sitting? Normally power washing would be done on it. I’m selling my home and the realtor gave me things to do to prepare it for a buyer. The poconos in PA is woodsey and while it’s beautiful, it’s also requires maintenance. Thanks Dom.

Hey, Dominick Great Video and info.
Just went through all your posts and reply’s.
Amazing that some people cannot follow simple directions?
You must have sore eyes and chest muscles since you have to roll them and sigh with frustration so many times.
Thanks for the good work.
Rich

I didn’t like the feedback from buyers on ebay so I didn’t post the link. 2 gallons of H20 to one gallon of sh.

Raymond McgeeApril 14, 2014

Hello Dominick. Did you get the link to e bay. if not you will find it on e bay under sodium Hypochlorite . I used to work in a carpet factory and we used to get industrial bleach for removing thick dye
from printing screens when washing. This stuff would set fire to cloth in its undiluted state Powerfull How much water do you recommend per ltr for the 14% I bought Thanks for your help Raymond

I really can’t answer that. Your dog eat some rat poison the same time you’re cleaning your roof and it’s my fault. Sorry. Just spray and rinse well. SH is a high power bleach. And bleach would kill if you swallow it, right.

Sam BMarch 26, 2014

Will the SH solution be harmful to animals? If I leave the liquid on the roof and spray the moss off after it drys will it be safe for my dog in the yard?

Calcium comes in a dry form. SH does not. Calcium won’t do a thing as far as cleaning a roof. So yes you must use a SH.

Rudy OakesMarch 6, 2014

What is the major difference between using Sodium Hypochlorite vs. Calcium Hypochlorite… other than one is sodium and the other calcium, will they have the same effect?… and you did specify using liquid , not mix your own from dry right?

Hi, yes over time it will flake off. However moss can be a real bitch. A little help with a broom would be a big help. Glad to hear you’re better now.

Rudy OakesMarch 6, 2014

Question about clearing 2 years of moss and “stuff” from the roof…love the video… was in the mode to clean the roof 2 years ago, long story short, had cancer removal and was off my feet for about 2 years… and well… the roof needs help. I am not physically fit enough to scrub the roof, however, I an probably spray the roof … Here in Oregon, letting the rain was away the residual won’t be an issue, the question I have, this kills the moss and “over time” if left unattended.. mother nature should just “was the surface clean” right? or do I have to get someone to get up there with a broom? thanks

Brush the moss off, Then spray the roof with the cleaner then rinse after 30 minutes.

steveMarch 2, 2014

My question is regarding using the “pool shock” treatment on a low pitch, tar, pea gravel roof. I can’t just brush the moss off so do I leave it on until it’s dead and rake it out? Will that damage anything? Do you have any suggestions?
Thanks

I would go with with a 50/50 mix. Just make sure you rinse very well. SH will kill everything in it’s path ie. plants and stuff like that. Yeah the setup my son uses is very cool. It uses air pumps with 300 feet of hose. Holds 200 gallons of SH and mixed per job right on site. And that whole system was made a designed by me. Took sometime to get it right.

Dave LivingstonFebruary 20, 2014

Hi Dominick, thanks for the quick reply.

I should have said before that I was referring to your video of “How to remove moss from a roof” on YouTube instead of the one on this page.

That shingle roof you cleaned in the video had a similar amount of moss as my concrete tile roof, like a carpet. In December I used a wire brush and scraped of the bulk of it so now want to spray to kill the rest off.

Would you say a third SH to two thirds water would work for my 14% SH and a squirt of dish soap? Or 50/50 mix? As you say, best to have a stronger solution so it works.

Also love your hose spray for the SH in that video, I’ve not been able to find anything similar in the UK to that.

14% very nice. Use it just the way I show. Maybe you could add a little water if you wanted to. But for the most part what I showed is for mold “black stains” So for the moss you would want something stronger anyway.

Dave LivingstonFebruary 20, 2014

Hi, I’m in the UK and need to spray the moss on my roof (covered with rough Marley concrete roof riles).

I can only find SH in 14% (available chlorine) strength sold in 2.5 UK litre containers, so I’ve bought two.

Could you give me some help on how much SH, water and liquid dish soap to use since this is a stronger solution to mix up, for say one US gallons worth of cleaner solution at a time?

I don’t have a big capacity sprayer or containers, so will mix up smaller quantities about 2 or 4 UK litres as and when required. I’ll be able to convert to UK litres (using 1 US gallon = 3.78541 UK litres) but am unsure of the amounts since this is a higher strength.

That seems way too high of a price. And no, without spending big bucks on air pumps and special equipment. Send me a picture of your house and I’ll tell you what it should cost.

JohnJanuary 31, 2014

I’ve received three quotes, and the price each is $1200-1300 which is out of my budge. My roof is a 10:12 pitch, and somewhat steep. I am trying to figure out a way to spray it myself, without too much mist and overspray, while standing on a ladder. I noticed Northern Tool has “tree sprayers” that shoot 2.2GPM or 5.5GPM out at 60psi.

Do you have a solution where I can do this myself from the ground without walking the roof/

So glad I found this. I’m purchasing a home and thought the roof was in need of replacement. The roof has that ugly black stain but only on the North side as you said. The other side looks brand new. I’ll be using these techniques right after moving in!
Thanks!

At what temperature does the mixture start degrading? I live in New Hampshire and have about 1/3 of my roof in moss, thanks to some Maples. I’d like to clear the moss as soon as possible to save money on my insurance, but am concerned about the temperature.

Thank you. It really depends on how dirty your roof is. The SH will die once the heat gets to it. So no worry there. With the first app if the roof is clean, leave it. Gives better protect if you leave it on.

TomNovember 6, 2013

When is it advisable to rinse vs no rinse, or is it safe to never rise. Doesn’t the dry material left on roof have a chance to leach heavy amounts of product in a rainstorm to down spouts after the initial appl, and plant lawn heavy rinsing has been done. Also could you repeat a few appls during the day for stains etc with no ill effect. Thanks for your input and bty GREAT SITE

BessieNovember 4, 2013

How old is the question or how old is the roof? The roof is at least 18 years old. The question is current. We will not be able to work on the roof until settlment that is in early December this year 2013.

Will this work in the cold weather? My husband and I are going to settlement on a summer home in northern PA in December and we can’t get homeowners with all the moss on the roof. We have to agree to get rid of it ASAP after settlement. We plan on a new roof in spring anyway.

Yes very much so. You really need it stronger. I can’t tell how many times I’ve seen that before. It really does make that much of a difference. Without seeing your roof it’s a little hard for me to say. And thank you very much. I do work my butt off on this site. Like right now at 5:55am lol…

LaurieOctober 26, 2013

We tried the solution on our roof which is pretty old 20+ and did not see a big difference. Could be the roof is permanently discolored. I was also wondering if the solution it self might be the problem..it says 10.5% instead of the 12% you recommend. Would the 10.5% be the problem? That’s what our local pool supply had. BTW your website is amazing can’t thank you enough.

Try a third of SH and the rest water.. or for a stronger mix use 50/50

JohnnyOctober 25, 2013

I have a 1 Gallon bug Sprayer. I don’t have a 3 Gallon one. If i mix 1 gallon of liquid pool shock with two gallons of water inside a 5 gallon bucket. Can i pour 1 gallon at a time into my bug sprayer.. Will i mess up the ratio? Thanx for the help

Using hot water will kill the SH. Use the water out of your faucet. Rinse the moss off.

ShamuOctober 23, 2013

Hi Dominick,

We are going to try a bleach and water solution on our roof to get rid of the moss. Any advice you can offer would be appreciated! Should we rinse the roof off with water after the bleach has been sprayed on? How long should we let the bleach solution sit there? Thanks!

No not really. Unless it was super dirty. Just make sure you rinse the plants very good. And yes very true about the salt. But with a kick LOL..

GeorgeSeptember 29, 2013

I know it was asked but if im using sh do I need to rinse the roof? I don’t want any plants or landscaping to die when it rains and all the dired sh runs off the roof. Dried bleach is still salt and salt kills plants and grass I think. Thank you for your input on this. George

NicholeSeptember 9, 2013

Just want to say…you are awesome! We are about to purchase a 1920 home and I have been watching all your videos for DIY….the best out there! Thanks a bunch for doing this! Cleaning my roof will be one of the first things I do!! (then finishing the rewiring of old knob and tube the previous owner started…yikes!)

Yes I could. However not for free and would be done via email / phone and pictures of how to setup a trailer or van. $500. and make it back in just one roof job.

Harold MoorefieldAugust 25, 2013

Could you tell me how I could go about starting a business doing this? Like how much to charge and what type of setup you are using in the video?

Valerie FloweAugust 19, 2013

We tried this technique over the weekend. I was amazed at how quickly the moss died. I left it on for a day. I used a brush to loosen some of it up. After I rinsed the moss off, there is still a fine light green ‘moss fuzz’ on the roof. Not sure if I should try and scrub it off? I don’t want to strip the rocks off the shingles and cause the roof to leak. Suggestions?

RandyAugust 12, 2013

Hi,
I have a camp in a very remote area of Maine. It is covered with moss. I am curious, should I simply use your suggested solution (Pool Shock with Water and dish soap-surfactant) and then brush? I don’t have a hose and spigot handy, so I cannot rinse off the solution after spraying it on with a pump sprayer. Any other suggestions would be great. Oh yea, and I’m going to use the copper flashing for future moss elimination.

Hi, could you tell me what mixture you use for power washing vinyl siding? Thanks

DaveJuly 13, 2013

this will get rid of moss on the roof also?

DerekJuly 4, 2013

For roofs that have a heavy buildup of roof moss, can you add some copper sulfate to the mix (aprox. 1/8 cup)to kill the roots of the moss so you would not have to scrub the roof but simply rinse with a hose.
Thank You
Derek

DeanJuly 3, 2013

How large of an area will a 3gal batch of cleaner cover?

GlennJune 30, 2013

Will this work on siding as well? I have some green algae growing on my siding near the ac unit. Can i use the same spray, wait, and rinse method?

KevinJune 20, 2013

Thank you for the video! My fear is that the roof will stain. I am more concerned about the shingles than the grass.

MarieJune 7, 2013

Hello, Just wanted to let you know the roof cleaning solution worked great.
Two roof cleaning companies wanted to charge between $700-$800. Your method cost us a total $6.24 Thanks

You can. For the most part we don’t. However if your roof comes clean in under five minutes then it’s to strong. So then yes you would rinse it. Five minutes is a good number to go by and then you don’t need to rinse it.

Yeah sure. It’s all about the mold on the roof you’re cleaning. However on cedar you MUST really rinse it good.

DanMay 22, 2013

Hello, I was just wondering if this solution would work on any other type of roof, like clay tiles or cedar shakes and stone slate roofs. Thanks

CJMay 22, 2013

Is the SH formula the same one you used to remove moss as well?

Tilmon DuguayMay 21, 2013

hi dominick if we buy the sodium hypoclorite liquid do we have to mix that with water ….what i exactly need for 10 gallons of water if i use liquid sodium hypochlorite

Tilmon DuguayMay 21, 2013

hi can you email me the name of the liquid pool shock brand name please and a bottle of that is already mix with water. do i have to add more water ….and i want to know for 10 gallons of water i will have to put 5 gallons of liquid shock for pool and thats gonna work to clean the black mold and the algae on a roof

JoshMay 19, 2013

Do you rinse the solution off and how long do you wait?

GeorgeMay 13, 2013

My question is when you rinse off the roof, Does the gutter runoff from the shock hurt the lawn (I’m guessing it doesn’t as long as it isn’t 95 degrees out)?

Appreciate you explaining this process to fix a problem many of us have! Thanks, George

One would think so. However this is a very common mistake. You are thinking outside the box. It’s very important that you mix it the way I stated. This is by weight. not by volume like baking a cake.

RonApril 4, 2013

This might be a silly question, but if you are diluting the 1 gallon of pool shock that is 12% SH with 2 gallons of water, doesn’t that reduce the % of SH to 3%? Which is less than bleach that is 5-6% SH?

I am having trouble locating the 12% sodium hypochlorite. Is there a site online I can order it from? Keep find calcium hypochlorite anywhere from 48 to 90%. Thanks.

adminMarch 18, 2013

Over time that would or could work. But you could be adding to much water to the mix at that point. However the SH would end up eating your power washer. The best wat is to stand on the gutters edge for a pump up system. Something like what Roof Sparkle uses. Unfortunately that info I can not give out just yet. And needless to say it’s not cheap. And the over spray you would get from a power washer would be way to intense.

leroyMarch 17, 2013

I have a very steep and dangerous multi roofed home in the Puget sound area. Walking on most of my roof is impossible because there no anchors. Your moss killer sounds like what I need as I am starting to get a carpet on the north and west sides. I have a pressure washer that has a small tank on it that could deliver the stuff onto the roof. I just wanted your opinion on putting it on that way. will that work with the really wide attachment. Thank you for your help. Leroy

adminMarch 13, 2013

When we go out to clean a roof there is always two guys on a job. One is the guy on the roof spraying / cleaning the roof and the other ones job is to spray everything and anything that could get over sprayed with the roof cleaner.

So, you would wet down all plants and then rinse them again once you’re done cleaning the roof. We clean roofs all day long. But once in a while it just gets way to hot. At that point you really can’t walk on the roof anyway without damaging it because it’s way to soft. Hope this helps… Dominick

SamMarch 13, 2013

How do you keep the bleach from hurting the plants, grass or leave obvious streaks on surfaces below?

Is it best to clean the roof then in the AM or PM, after the sun goes down sometimes the roof remains hot for well into the night.